I have a non-RV aircraft with a Rotax 912ULS. The drip trays are cracking. The Vans style looks very interesting and I think it would fit my experimental. I looked on the web site but didn't see a way to find or order them. Can someone tell me how you would get a replacement drip tray if you needed one?

Thanks for the Rans tip. I may have a clearance problem on that one but will check it out. I had seen the Vans graphics referred to and it looks like one could simply make one up one's self and seal them with fuel tank sealer.

The Drip Tray for the Rans looks to be the Rotax drip tray as seen in the parts manual and here at CPS. Given the way Vans has you construct the drip tray it seems to me to be a little less susceptible to cracking (the carb / intake manifold plates are doubled).

It raises a couple questions for me though:
1) Both CPS and the illustrated parts manual say this should be used when the air box drip pan isn't used. (CPS diagram states not suitable for direct installation of the air filter on the carburetor. Foreseen for air boxes without drip tray - this may be dated - it doesn't say this in the current parts catalog - r.e. - g).
2) The gasket arrangement shows a paper gasket between the intake and the carb flange and the O-Ring between the flange and the drip pan.

The surfaces of the intake and the carb flange are grooved for the O ring. Vans has you put the O ring against the intake and the drip pan. I assume they felt that since the carb flange was rubber it would seal good enough. I'm just curious about why the illustration would not have been followed from Rotax when designing the drip trays for the 12.

I haven't found any hard requirement from Rotax to have a drip tray - only the contrary statement from the CPS parts breakdown. I think it's just common sense to do so since it's sitting directly above the exhaust and helps to shield heat - not sure the Vans would stop a fire since any significant amount of fuel would just run off the back.

The Rotax drip trays are $102 each from CPS - I'm sure Vans would sell you their parts for much less - one of the things I love about Vans Aircraft.

Anyway - just thinking about this since Scott mentioned that the only engine meltdown they knew of happened as a result of the O ring not being properly installed during assembly of the drip pan.

If the carb mount is removed from the manifold so that it can be inspected, a raised area around the flow path hole can be seen. It is basically a molded in O-ring that will seal on the aft side of the drip tray (if installed).
There is an o-ring in a groove on the intake manifold that seals the fwd side of the drip tray.
If no drip tray gets installed, the manifold o-ring compresses on the flange of the carb. mount producing a double seal.
In the case were the o-ring was incorrectly installed, the builder moved the o-ring from the grove in the manifold and attempted to put it in the very small grove that surrounds the integral seal of the carb. flange. It does not fit... so it squirted out during installation.

The statement "this should be used when the air box drip pan isn't used" actually is indicating that a drip tray is required. The airbox they are talking about is this..
It is produced and sold by Rotax and is very expensive. It attaches to the back of both carbs and does away with the need for a drip tray because it is a closed plenum that has nipples for connectiong the carb vent tubes to. Note that it does still have a heat shield for each exhaust pipe that has a place for drain hoses which to me are pointless because any fuel that ever drains from the carb will go into the airbox. So what they are saying is if you are not using the airbox, you should use the drip tray.

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